The Effect of Oxygen Tension on the Differentiation of Outgrowth Cells from Embryoid Bodies Produced by Mouse Induced Pluripotent Stem Cells

The purpose of this study was to investigate the effects of oxygen tension on mouse induced pluripotent stem (iPS) cells by assessing differentiation in terms of embryoid body (EB) size and mRNA and protein expression levels of collagen type 1 and Runx2. EBs and outgrowth cells (OGCs) were cultured in conditions of hypoxia (2%), normoxia (21%) and hyperoxia (35%). Significantly larger EBs were observed in the hyperoxia and normoxia groups compared to the hypoxia group on Days 8 and 10. The hyperoxia group had significantly higher mRNA and protein expression levels of collagen type 1 and Runx2 compared to the hypoxia and normoxia groups on Days 10 and 26, and these expression levels in the hypoxia group were significantly lower than the normoxia group on Days 10 and 26. These results suggest that hyperoxia accelerates the enlargement in EBs and the differentiation of iPS cells.